Potentially toxic elements (PTEs) discharge to the soil environment through increased anthropogenic activities is a global threat. These PTEs can have harmful and chronic-persistent health effects on exposed populations through food consumption grown on contaminated soils. Efforts to investigate the transformation mechanism and accumulation behavior of PTEs in soil-plant system and their adverse health-effects have focused extensively in previous studies. However, limited studies address biochar nanosheets (BCNs) as a potential soil amendment to reduced humans health risks through dietary intake of food-crop grown on PTE-contaminated soil. Here, we showed how BCNs cutback health hazards of PTEs through impacts on bioavailability and phytoaccumulation of PTEs, and their daily intake via consumption of wheat. When BCNs amendment was compared with both conventional organic amendments (COAs) and control, it significantly (P ≤ 0.05) reduced bioavailability and uptake of PTEs by wheat plants. Based on risk assessment results, the hazard indices (HIs) for PTEs in all treatments were < 1, however, BCNs addition significantly (P ≤ 0.05) reduced risk level, when compared to control. Furthermore, the cancer risks for Cd, Cr and Ni over a lifetime of exposure were higher in all treatments than the tolerable limit (1.00E-4 to 1.00E-6), however BCNs addition significantly suppressed cancer risk compared to control. Conclusively, our results suggest that BCNs can be used as soil amendment to reduce potential risks of PTEs through consumption of food grown in PTE-contaminated soils.

1.a Research Group for Advanced Carbon Nano-materials and Reaction Chemistry of Pyrolysis for Sustainable Environment, CAS-Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, PR China2.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi’an, Shaanxi 710075, China3.Soil, Water and Environmental Chemistry Laboratory, Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad 38000, Pakistan4.School of Resource and Environment, Anhui Agriculture University, Hefei 230026, PR China